“Zonnetje” 2022 Winner – Brede Groene Dijk

Every year at the National Delta Congress, the Delta Programme Commissioner presents the “Zonnetje,” the prize for an appealing project that can be a shining example for others when it comes to effective, innovative and promising implementation of the Nationaal Deltaprogramma.

Delightedly this year the Brede Groene Dijk project was selected as top three, alongside two other projects focused on climate adaptation in the Netherlands. One project, Climate-adaptive redevelopment of Zwolle station area focused on making the station area climate-adaptive in extreme rain showers and heat. The other project was the Freshwater region Freshwater supply Eastern Netherlands, that focuses on preparing the eastern Netherlands for (extreme) dry conditions.

The Brede Groene Dijk is the world’s first sea dike made of salty dredged sediment. The sediment has matured into solid dike clay in three years, a process that takes many years in nature. The dike has been widened and raised with this special clay over a length of 750 meters. From 2025, the local water authority also wants to reinforce the remaining 11.75 kilometres of the sea dike along the Dollard estuary with this local clay.

EcoShape is excited to share that the winner of the “Zonnetje” 2022 is the Brede Groene Dijk!

Delta Commissioner Peter Glas: “The wide, green seawall is a good example of innovative Dutch hydraulic engineering. We will have to strengthen many dikes in the coming years. This project shows that it can be done smarter and more sustainably. It is a green dike that fits nicely in the Natura-2000 area. Because we reinforce the dike with clay from the neighbourhood, we avoid long transport distances; we reduce CO2 emissions from transport and at the same time, we improve the water quality because we use the sediment from the Ems Dollard. As a Delta Commissioner, it is also important for me that this sea dike can be easily adapted to a rising sea level. You don’t have to remove the asphalt first, apply sand and then resurface. You can just put extra clay on it.”

Collaboration Creates Success

Waterschap Hunze en Aa’s is the client. EcoShape (Deltares, Van Oord, Boskalis) has constructed the dike and is monitoring it. The Provincie Groningen, Rijkswaterstaat, Stichting Het Groninger Landschap and Groningen Seaports are partners. The project is part of the Programma Eems-Dollard 2050 and the Nationaal Deltaprogramma. Waddenfonds and Hoogwaterbeschermingsprogramma (National Flood Protection Program) are the financiers. In the National Flood Protection Programme, the water authorities and the central government are working together on the largest dike improvement operation since the Delta Works: 1,500 kilometres of dike will be reinforced over the next 30 years.

To learn more about the Brede Groene Dijk visit: https://www.ecoshape.org/en/worlds-first-in-groningen-sea-dike-made-of-salty-dredged-sediment/

To learn more about the other two projects visit: https://www.deltaprogramma.nl/nationaaldeltacongres/2022/zonnetje